For the next month, Earthlings will be treated to a spectacular sight, with all five planets visible to the naked eye lining up together, stretching from the horizon to the moon. But just don’t call it a “planetary alignment”.

For those in the southern hemisphere, if you look towards the north you should be able to see Mercury, then Venus, Saturn, Mars and finally Jupiter stretched out from the horizon, just before sunrise.

Venus and Jupiter will be easy to see, being the brightest objects in the sky, according to Prof Fred Watson of the Australian Astronomical Observatory. Mars should also be easy to spot because of its distinctive red or golden colour.

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“Saturn is between Mars and Venus, so it’s lower down,” Watson said. “It’s the one you’re most likely to confuse with stars because it’s not as bright as Jupiter. But it’s yellowish. And with binoculars with about 10 times magnification you can tell it’s not a round dot of light like a star – it looks elongated.”

Mercury could also be tricky to see because it will be close to the rising sun.

Those in the northern hemisphere should look south just before sunrise.

The reason for the unusual astronomical sight is that the five planets happen to be on the same side of the sun at the same time, says Alan Duffy, an astrophysicist at Swinburne University.

That means the planets can all be seen in the morning, rather than some of them being visible in the evening.

Because all the planets sit on a single plane, and we’re looking at them from inside that plane, they will all appear to be sitting in a line.

But it wasn’t strictly a “planetary alignment”, Duffy said. That was a term used to describe a situation where three or more planets are sitting in a straight line when viewed from above the solar system.

Stargazers will get another chance to see the sight in August when all five planets will be together again, only this time on the other side of the sun, meaning they will be visible just after sunset rather than before sunrise. It will not happen again until 2018.